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Primary reference(s)

Rossetto, T., 2013. . Accessed 29 November 2019.

Additional scientific description

Structural failure affects both standing and underground structures, including bridges, canals, viaducts, buildings, tunnels and pipelines. This exceedance may lead to more widespread progressive collapse. Progressive structural collapse is defined by the National Institute of Standards and Technology (NIST) as the spread of an initial local failure in a manner analogous to a chain reaction that leads to partial or total collapse of a building (Ellingwood et al., 2007). Different types of progressive collapse have been referred to as pancake, zipper, domino, section, instability and mixed (Starossek, 2007).

Metrics and numeric limits

The United Nations Educational, Scientific and Cultural Organization (UNESCO) lists 63 countries with seismic design building codes, both members and non-members (UNESCO, 2019).

Many countries have standards on progressive building collapse, these include the European EUROCODE (European Commission, 2020), Canadian National Building Codes (Government of Canada, 2015), and Swedish Design Regulations (Boverket, 2018).

Examples of drivers, outcomes and risk management

The drivers of structural failure can include design defects by engineers or architects, incorrect or substandard construction materials, inspection failures to identify building and construction problems, as well as natural hazards or a combination of these drivers (Almarwae, 2017).

Three summary examples follow:

• The Minneapolis bridge collapse that occurred in 2007 is an example of a structural failure that resulted in people being killed and seriously injured. The root cause of this event was exceeding the original structural load-bearing design by retrofitting additional road transportation lanes at later stages and also the weight of road maintenance equipment on the bridge on the day of the failure (Hao, 2010).
• The Heathrow tunnel collapse in 1994 was attributed to the implementation of new project management frameworks, exceeded tolerances of tunnel deflection, inadequate repair to ground settlement, and lack of inspection and monitoring in the construction of the tunnel (Wood, 2000).
• The Sasago tunnel collapse took place in 2013, where a large section of the suspended ceiling panels fell onto moving traffic. This caused the deaths of nine people and the failure was identified as the deterioration of the tunnel construction over time and a lack of routine maintenance (Fujino, 2018).

The Occupational Safety and Health Administration (OSHA) states that rescue workers and emergency responders may already have experience with entering collapsed structures resulting from construction catastrophes, earthquakes, fire and weather-related structural failures. Weather-related structural failures typically result from rain/snow accumulations on roofs, hurricanes, tornadoes, landslides and even avalanches. Rescue workers and emergency responders also face the possibility of entering a structure that has collapsed following a terrorist attack. Terrorist activity may add additional hazards such as secondary devices, follow-on attack and residual radiological, biological or chemical contamination. Historically, terrorist activities that have resulted in collapsed structures include crashing commercial jets into the World Trade Towers in New York City (11 September 2001) and vehicular bombs, such as the one used at the Murrah Federal Office Building in Oklahoma City (19 April 1995). Regardless of the root cause of the structural failure, rescue workers and emergency responders who enter a collapsed structure in order to perform their duties should be able to work safely (OSHA, no date).

The effects of building collapse include impacts on lives, livelihood and health as well as social, economic and environmental impacts. Since the United Nations International Strategy for Disaster Reduction launched its campaign kit for making cities resilient (Ä¢¹½´«Ã½, 2010), the United Nations Office for Disaster Risk Reduction has been committed to making cities resilient and has engaged and published widely including sharing the ten essentials for making cities resilient (Ä¢¹½´«Ã½, 2019). Engagement in this campaign is vital for enhancing the drivers for risk management with ‘Essential Four: Pursue Resilient Urban Development and Design’, which calls for integrating resilience into socio-economic development planning and infrastructure to safeguard development investments – which will help to reduce the risks of building collapse (Ä¢¹½´«Ã½, 2019).